Oil-cracking process



'May 2l, A. SCHWARZ 1,714,453

OIL GRACKING RocEss Filed March 25, 1925 PaMP /645 Pnooucfn. I 7

W XW, fjwuanc ranma May 21,1929.l

UNITED STATES .l 1,714,453 PATENT orner..

ALFRED SCHWARZ, OF QPPER MONTCLAIR, NEW JERSEY., ASSIGNOR TO COAL ANDOIL PRODUCTS CORPORATION, A CORPORATION OF DELAWARE OIL-cnnoxINGPROCESS.

applicati@ mea Marcil 25, 1925. sealan. 19,076.

This invention relates toa process of cracking oil thereby producinglighter oils and gas therefrom. It relates more parJ ticularly to aprocess by which theoils may be cracked and the carbon resultingtherefrom can be utilized in the process.

In processes now commonly used for producing 'motor fuels from oils thathave higher boiling points than those suitable for motor lfuels, whichprocesses are called oil cracking processes, it is more or less commonpractice to crack the oils thereby producingresidues in the form of cokeor heavy tarsof little commercial value which are oftentimes expensiveto handle and hard to remove from the apparatus in which they areproduced. Furthermore, in cracking oils the heat transfer isi usuallymade through the walls of receptacles which procedure is wasteful andfrequently. causes deposition of carbonaceous matter upon the heatingsurfaces.

One of the objects of my invention is to crack oils in such a mannerthat Apractically all of the heat supplied to the oil is intro-v duceddirectly into the oil withoutpassing through the walls of thereceptacle. An-

other object of my invention is to so control the chemical compositionof the gases produced as to have a maximum of compounds of a hydrocarbonseries other than the parahn series, and preferably those bf the benzolseries. A further object of my invention is to consume the residueformed during the operation so as to generate heat and gases in order toeliminate the handling of residues and in order to be able to cracksubstantially all the oil and to convert -any such portion of the oilthat may have a tendency to be precipitated as carbon,into y a fixedgas, this gas being a secondary product of the process.

The invention will be understood from the description in connection withthe accompanying drawings, in which two arrangements of apparatus areshown by'which the process can be performed. Ingthe.draw

ingsFig. 1 is a somewhat diagrammatic view showing the arrangement ofthe apparatus, parts being shown in section, to carry out the processand Fig. 2 is a similar view showingA a modied arrangement ofAapparatus.

lIn the drawings, reference character 1 `indicates a gas producersomewhat similar to forced into the those commonly used, the same beingmodified, however, so as to adapt it especially for carrying out thepresent-invention. The producer 1 has a main chamber 2 which may belined with fire-brick, and a superposed chamber 3 having a waste heatduct 4 extending therefromprovided with a valve 5. The chamber 3 isclosed at the top by a cover 6 which carries a perforated plate to serveas an oil distributor: as indicated below. A coal hopper 7 controlled bya valve 8 leads to the chamber 3 andthe hopper 7 is supplied from asupply 9 that is provided with' a valve 10 that may be opened andclosedat will for feeding a charge of coal to the hop er 7. c

T e producer 1 is also provided with a grate 11 below which steam may beintroduced into the producer through the valve controlled inlet pipe 12from any convenient source. A valved pipe 13 leads from the prodcer 1tangentially into a settling cham- .y ber 14 that is provided with anoutlet pipe 15 controlled by the valvel'. A pipe 17 leads from upperportion of the settler 14 to a rfractionating tower 18 which is rovidedwith the usual shelves 19. This filiactionating tower may also befilled, if desired, with porous material such as coke, broken brick orthe like. Reflux pipes, one of which is shown at 22, lead from theshelves to the lower end of the fractionating tower and a valvedbranchpipe 23 leads from the pipe 22 into the tower and a valved branch 24 maylead to a storage or supply tank. A pipe 25 leads from the fractionateoving tower 18 to a condenser 26 that may be thriougha pump 35 toa gasholder not` shown. If desired two producers l may be connectedl to thetower 18, the same being operated alternately.

A branch pipe 39 provided with'a valve 43- leads from the pipe 12 to theinjector 40. The suction end offithe linjector 40 is connected by avalved pipe 41 to the suppl' tank 42 for` oil that is to be cracked. 105pipe 46 leads from the injector 40 to the cover cap 6. They oil-i-fromtank 42 ynay be isproducer 1 by means of the-injector 40 w en gravitfeed is not provided'or a pump mayfee the same. The 1'10 starting thefire in the producer 1.

In the modification shown inV Fig. 2 many of the devices are identicalwith those already described i'n connection with Fig. 1 and such partsare indicated by the same reference character with the suiiix a. Thisarrangement differs in certain respects from that shown in Fig. 1. Theoutlet pi e 4a leads into a heating chamber 50 in whlch a still 53 isplaced. This still is provided with tubes 51 which tubes lead to a stack52. A valved pipe 55 leads from the still 53 to.the valved pipe 17, thatleads directly from the gas producer 1u to the fractionating tower 18,.the tower 18? being provided with a vapor outlet 25a in the upperportion thereof. One or more valved reflux pipes 22 lead from theshelves 19 to points below the liquid level in still 53. Two ormore gasproducers l may be connected to the still 53 and the fractionating tower18a and operated alternately. A pipe 41a leadsfrom nearl the bottom ofthe still 53 through a pum 57l to an injector 40% Steam may be admittedto the injector 40a through the pipe 39a from any convenient source anda pipe 46a leads from the injector to the cap 6a of the gas producer.

The upper end of the tower 1 8 or 18a may be jacket'ed and the supply ofwater thereto may be controlled or regulated by means of valves as shownat' 6() so as to' introduce steam or water around the upper portionthereof. A

The process may be operated in two ways which may be termed continuousand intermittent respectively. In operating by the so-called continuousmethod, fire is started in the producer l onl the grate 11, coal or cokebeing then charged into the ,chamber 2 until it is filled nearly to thevalve 8. The blower47 is started with the lvalve 5 open and the valves8, 3G, 38, 43, 44

vand'superheated' steam is admitted through valve 44 into the injector40, while oil is `admitted from the tank 42 into the injector 40 so thatthe atomized mixtures are sprayed through'the cap 6 into the chamber 2where the coal in the upper part of the reducer acts as a temporaryretainer for t e oil and the high temperature in this region will beginto crack the oil. Thevaporstherefrom will pass. downwardly into a hotterregion where more cracking will take place and carbon will be deposited,the vapors or gaseous products ,finally passing into the pipe 13 andthrough the settling chamber 14 where suspended particles 4will bedeposited and the vapors will then pass through a pipe 17 into thecolumn 18 where the vapors are fractionated, the uncondensed portionpassing through pipe 25Aand condenser 26 whereupon the uncondensed gasesand the condensate-pass into the receiving tank 29 where the watersettles to the bottoni and is Withdrawn through the pi e 30 while theoil is Vwithdrawn through t e pipe 31 and the fixed gases pass throughthe. pipe 34 and pump 35 to a place of Iconsumption or to a gas holder.The reflux pipe 22 is arranged to lead the reflux from a plate 19 to thebase of the tower where it ican be introduced into the hotter'portion ofthe tower through the pipe 23, or it may be withdrawn through the pipe'24. When introduced into the hotter portion of the fractionating tower18, the condensate comes into Contact with the hot gases from producerfrom separate plates 19, the condensates passed therethrourrh will beoils of differ# ent specific gravitles and different qualities which maybe subjected to further treatment in the tower 18, or they may bewithdrawn from the 'system for other uses. .The lighter oils will, ofcourse, be drawn from the top shelves 19 of the fractionator and heavyoils from lower shelves. `The heavy oils that may be withdrawn throughthe pipe 2O may be passed through the system again by rst introducingthe same into the supply tank 42. While operating the process as abovedescribed, air is constantly taken into the system which is first causedto produce carbon dioxide in the lower part of the gas pro-y ducer andwhen the proper amount of air is introduced this carbon dioxide isconverted into carbon monoxide in upper layers of the incandescent coalor coke. Superheated steam is admitted through the pipe 12, and formswater gas in accordance with the Well known reaction and the combinedgases meet the oil vapors that pass downwardly through the upper portionof -the producer and the mixture passes through the line 13 as aboveindicated. Reactions appear to take place between the ases andvapors,but on account ofthe fact t at there are so many differenthydrocarbons present in the mineral oil vapors, the reactions of4 whichare very com licated, it is not certain what the various c emicalreactions are in the different reaction zones.

-Thefollowin is given as an illustration of results that i ave actuallybeen obtaiii'edI with an installation of this character. With a gasproducer' 1, about 7 high and 14 in internal diameter and afractionating tower 18, about 14 high and 12 in diameter arranged asillustrated in Fig. 1, I charged the producerwith ordinary foundry cokeand raised the temperature to about 800 F. and charged superheated steamthrough pipe 12 at a temperature of about 600 F. A vacuum pump of theeccentric piston type was set in operation as shown at and a smallamount of air was admitted through the valve 49. Petroleum oil having aboiling point such that about 12% -could be distilled off between 500-F. and 600 F., the remainder boiling above 600 F., was introducedthrough the injector throughthe spray box 6. This oil was the residuefrom a pressure cracking operation Ycommonly called pressure still tarin the trade. The

process was operated for several hours and during that entire time gasesobtained from the receiver 29 burned with a high caloriic value anddistillates collected from the pipel 31 contained 65% of material thatwas distilled ofbetween 120 F. and 437 F. and

60% of the remainder distilled below 600 F.

When operating the process as just ndescribed, due to the continuous'admission of air, there appears to be .a considerable amount ofhydrocarbon derivatives formed of the fatty acid series. And thisconstitutes an important factor in the process. Such fatty'acids may berefined and used for many purposes, for example: Manufacture of soaprequires large quantities.' If the process is operated with a view ofmaking fatty acids as a by-product the continuous admission of air isdesirable. If however the rocess is operated more for the purpose omaking motor fuel, a large amount of fatty acids in the distillate isnot desirable. desirable to avoid the production of fatty acids, theprocess maybe operatedintermittently'by first blowing' airV by means ofthe pump 47 through the gas roducer-l and permitting the products o passout through the pipe 4 until the temperature has reached the properpoint after which the air can be shutoff andthe oil sprayed in and steamadmitted until the temperature needs to be increased a other'variationof my process is t at I may mix the oil with ordinary live steam andpass both of them through a superheater and then introduce thismixtureinto the distributor #6. When the rocess is operated without anair supply, during 'the time the oil is being admitted to the producer1, the

production of fatty acids is very nominal but during the time that airis being blown into the producer to raise the temperature ofthe carbontherein to incandescence, a certain amount of heatA would be wastedlbutI utilize such heat, by arranging the apparatus .the A.pro ucing carbonmonoxide gas and relying combustion to in. An-

as indicated in Fig. 2. The products of combustion pass in thisarrangement of apparatus through the pipe 4a into the lire box 50 alongthe under side of thestill 53, which contains oil to be cracked, andthese products then pass through the tubes 51 where they give up furtherheat to `the oil and these products of combustion finally pass outthrough the stack 52. Vapors from the oil in the still 53 pass throughthe pipe 55 to the tower 18a and uncondensed vapors issue from thetowerthrough pipe 25u. Refiux condensate passes through the pipe or pipes 22afrom the' tower 18a into the still belowy the liquid level therein.After the `air has been blown into gas producer 1- a sufficiently longtime to bring the temperature to that of incandenscence, the air isshutfoi' ing conducted with the aid of steam which "is preferablysuperheated, I do not llimit myself to the use of steam as I may carryout rocess without using steam by merely upon the reactions among thehydrocarbon vapors, the gas being used as a medium of d,

heat transfer. The process is adaptable to many grades of oil and thereactions will vary with the sort of hydrocarbons used. Not only veryheavy oils and residues may be used-as the stock to be cracked, butlight oils such as kerosene and gas oil may also be treated 4by thisprocess. At the same time other sorts of oils such as coke oven lightoil, coal tar and the like may be introduced into the producer and ma besubjected to the treatment above descri ed. While the most logicalmethod of sup plying heat to the oil vapors and water vapors for thepurpose of inter-reaction, is to abstract saidheat from the gasproducer, nothin herein contained shall be construed to limit the scopeof this invention by the additional application of external heat on anyportion of the apparatus. While I primarily intend to extract thecombustible roducts from the fixed gases, in some cases may desire toconduct the mixed product to a burner or internal combustion engine .anduse all the products direct.

I claim 1. The process which comprises heating portions of a mass ofcarbon to different temperatures by combustion, bringing steam intocontact with a portion hot enough to form water gas, simultaneouslybringing hydrocarbon oils into contact with portions suiiicientlyheatedto form oil vapors, maintaining said vapors in contact with said mass ofcarbon, passing the same through zones of said mass of carbon ofincreasing ltemperatures suliciently hot to cracksaid -vapors andproduce a substantial amount of condensible hydrocarbons and suicientlycool to avoid complete gasification, mixing the water gas and oil vaporsat high temperatm-e and segregating the gaseous and lcondensibleproducts.

2. The process which comprises heating a mass of carbonaceous materialto an oil 'cracking temperature thereby producing .waste gases,utilizing said waste gases to heat a body of oil to a distillingtemperature, removing vapors from said body of oil, introducinvrunvaporized oil from said body into said mass of carbonaceous materialto eect vaporization thereof, passing ythe resultant vapors downwardlythrou h zones of increasing temperature to crack t e same,

fractionating the resultant ',vapors and gases, and conductm heaviercondensed fractions to said body o oil for retreatnient.

3. The process which com rises establishing a gas generating zone Eyblowin hot carbonaceous material -with air, heating a- ALFRED SCHWARZ.

